chicago



A. GELBERT. BESONANT DIAPHRAGM AN'D PROGESSDF MAKING SAME.

' Arrucmou man Ave-29. 19.19.

1,377,677. 1 Patented May 10,1921.

Waterproofing Films Hardened. qel'atinous disc,

re G/Aer @Z'ZFFQJ-"J; 0/ I 2. Q/M 0 umreoirs TATE'S.

PATENT" OFFICE.

mnnnonmnnimon ombnoognmntoxs, esszenon mo Amman onmlrrolln 1,130

'm'wonmsif-or orti oe eo, mentors. e ooneoneirronqor mum 01s.

meson-mm nmnnAem-niw moonss or Maxine em.

m'ezemew w m:

Boil; lino, n'thaz Lm omemeiu- .o'f th e'llInited $tates,'residing at Chi o,.' 11inois," have-invented eel-min new a usegul roven'ie'x'its in Reeonent l?ia'- phrall fis recesses of Me Salme; ,do hereby deolerethe following to be effull, clear, "and; eiact description of the m gnnomiea h as'wm, enebleothereskilled phrag'z'ns .oithe genera-l oli'zssivhioh includes L the, refiifoduee'r leoinxnonly used 'on m-lAtvpresengthe one material elnialoyed in lthe better gradeslof phonograph reproduci'ers for the needle-actuated dlnphrngm is gnic n which varies .Somuch 1n physioal strubturethat ibis priitioally 3msfEjble-1;o,.obtein two pieces exaLetly ahke .glyenwith the best grades of mice, the final:- ,ness de ilends partly on. the natural c1ea w age," so ,t at this willlvary to an extentwhmh .zoakes.'t difficult hxseoure any deslred d mension. Likewise, the brittleness of this mineral makes it impractical to go below a certain thickness for any iven diameter, thereby restricting the available floxibihty and ..elastioity, which is also llmlbed by the naturejofnthe minerall' Furthermore, the flakiness of the mica. is apt to cause particles to be detached from either .faoeof the disk, ,the, drilling of the disk for connecting it to ,lthe record-actuated .Ieyer is apt to damage it, and the nnea is newly scratched even by qaufingen -nuilu Such scratching or other d ity .0 desirability tirely useless.

' deoidedl impairs the tonal quaili t eu-disk, 1; us further linnting 1ts or even rendering the disk en- So also, the co1or.of the I micois redetermined by nature and cannot wradily' e altered to match the color schenze of the l. hon ograph without nnpmrmg lts banal qualities.

- Y My present mvention aims to overcome specification of Letters Patent.

, duh softening the. same.

ome 1921-.

1 1 1 e An ie; sen l nojseogle these and other :objeetionsbo theTinice-disks by promdlng disks which"'e'eii lreadil be mode 111 great umfo'rmity of tbiekness, yfiieh will be entirely homogeneous jinflst'ructure, E

which cennot eesily, be soratehed 'orjdaniaged, whrch mey be eolored as desired, which can readllybeout'diodrillod without ellip- P g or flaking'end whichjwill be, superior 111 ll fiutqi $11.19!, -fienera11y s wing,

l: attain these 41nd ,other" ob Producimg 'gelatmons'jdisk 1:bei 1 treating thus m such a ng nper asfiblmalze' it both reslhent and ,wetferbroof." Further objeets em a. peer iron: the 'follo' s eeifioatlon and, n e ccd pan ggfi iuing gin which iguro 1 been elejetlod'ofg phonogroph re p oducer' draghregmjmodefaiceordmi to myjmventlonl';

nlu stretive of y inv ehidoml mey fdlesolve four ounces of gelatin .in one quart of water with the aid dfheat, adding to this Y eel e le e lemnsv s ctio throughthe'serne, {1"

some 'ingredientgior hardening the prpduot during the subsequent evbpomtidn, es "for example "In; iiarter ounce- Inf manganese bombs." Or. may usenlurn'as the hardening ingredient, or both, and majt'art'xith some other gelatinous substance, such" 'as glue. ,Ii a. colored diaphragmis desired. I also qdd' zisuitable 'oolor'ing matter. The resultmg-mixture is then formed into-sheets.

either by floating it upon glass or by evgqaornting it in suitable pans or on netting. In either case, it is desirably passed between suitably adjusted, rollers before fit has entirelv lmrdened,.thereby squeezing out. any

air bubbles or gas bubbles which may be .due to .the chein ioal action ofa hardening mgredxent and also msunngthe desired oxnctness nsto the thickness of the resulting sheets. a By uarymg the em ountpf theherdemng lngredlent oxwingiedihts, I can readily produce sueh sheets ineny desired hardness. and in practice, Inmey harden the sheets to a degree consideribly in ex'oes's of that 'requiredfor efi'ording the desired resiliency and resonance, thereby -l-permi tti'ng nine to owaterprooitbe material-without un- WithoutQsueh, waterproofing, the gelatinous materiel ,ivould readil absorb moisture, thereby'eausmg it to swel andowur out of hardened gelatinous base provided on both sides with a more pliable coacting of a water-excluding gelatinous material.

5. A resonant diaphragm comprising a gelatinous base provided on both sides with a transparent and water-excluding facing.

6. A resonant diaphragm comprising a gelatinous base provided on both sides with a transparent and watenexcluding facing of greater pliahility than the said base.

7. A resonant diaphragm comprising a gelatinous base and a facing of transparent water-excluding material integrally united therewith.

8. The method of producing a resonant diaghragm which consists in softening the surface of a previously hardened gelatinous material.

9. The method of producing a resonant diaphragm which consists in softening the surface of a previously hardened gelatinous material by treating the latter with a mate rial also adapted to form a water-excluding facing.

10. The method of producing a permanently resonant diaphragm which consists in subjecting the face of a previously excessively hardened gelatinous base to a vaporizable li uid adapted to form a water-excluding eposit and containing an ingredient for increasing the pliability of the base.

11. The method of making a resonant diaphragm of predetermined resiliency, which consists in first producing a gelatinous material hardened beyond the desired resiliency, and then reducing the resiliency thereof by treating it with a softening agent adapted to form a water-excluding de osit thereon.

ignecl at Chicago, August 27th, 1919.

ALFRED GELBERT. 

